APPENDIX L Ridership Forecasting Technical Report Prepared by: VHB I-90 Allston Interchange Project Draft Environmental Impact Report Ridership Forecasting Technical Report TABLE OF CONTENTS INTRODUCTION ..................................................................................................... 1 METHODOLOGY .................................................................................................... 1 Key Assumptions .......................................................................................................................... 1 Transit Capacity Analysis Approach ........................................................................................... 3 Commuter Rail ...................................................................................................................... 5 Rapid Transit ......................................................................................................................... 6 MBTA Local Bus and Shuttle Bus ......................................................................................... 6 RESULTS ................................................................................................................ 6 Ridership ...................................................................................................................................... 6 Transit Capacity ........................................................................................................................... 8 SUMMARY OF IMPACTS .......................................................................................11 Ridership ..................................................................................................................................... 11 Transit Capacity ......................................................................................................................... 12 ATTACHMENT A CTPS Methodology and Assumptions of Regional Travel Demand Modeling Memorandum ATTACHMENT B CTPS Model Validation Process Memorandum ATTACHMENT C CTPS Transit Network Assumptions Memorandum ATTACHMENT D CTPS Land Use Assumptions Memorandum ATTACHMENT E CTPS Transit Crowding Analysis i I-90 Allston Interchange Project Draft Environmental Impact Report Ridership Forecasting Technical Report INTRODUCTION This Ridership Forecasting Technical Report has been prepared in support of the Draft Environmental Impact Report (DEIR) for the I-90 Allston Interchange Project (the Project). The purpose of this report is to document the methodology used to determine the ridership forecasts and associated transit capacity impacts for MBTA services and other transit services to be operating at the proposed West Station and in the study area to support the planning, environmental review, and preliminary design efforts for the Project. Ridership forecasts were developed for the future No Build and Build Alternatives, for the project’s 2025 Opening Year and 2040 Design Year. METHODOLOGY Ridership forecasts and transit capacity impact analyses for the Project were developed using standard transportation planning industry practice for the evaluation of transportation systems and infrastructure. The analysis was based on the development of existing conditions and future year travel demand forecasts provided by the Central Transportation Planning Staff (CTPS). CTPS is the staff to the Metropolitan Planning Organization (MPO) for the Boston Region and works with the communities within the region to address issues relating to transportation, land use, and economic development. CTPS develops and maintains the regional transportation demand model. CTPS’s method of travel demand forecasting follows the traditional four steps of trip generation, trip distribution, modal split, and travel assignment, and uses EMME software to run the travel demand model. A detailed summary of the travel demand model methodology utilized by CTPS is provided in Attachment A. Details of the process used to validate the regional travel demand model for the Project are contained in Attachment B. For the Project, CTPS provided a calibrated baseline, or existing condition, and developed No Build and Build Alternative ridership forecasts for the 2025 Opening Year and 2040 Design Year. CTPS also developed forecasts for vehicle loading on commuter rail, rapid transit, local bus, and shuttle bus services operating in the study area to analyze potential passenger crowding impacts. To support the ridership modeling and transit capacity analyses, the Project: • Provided CTPS with inputs for the development of ridership estimates, including future transit service levels and future land use data in the project vicinity. Descriptions of the service level and land use assumptions used for the modeling efforts are contained in Attachment C and Attachment D, respectively. • Reviewed outputs from CTPS and provided feedback to clarify and refine results. KEY ASSUMPTIONS The 2040 travel demand forecasts provided by CTPS assume the implementation of several transportation projects by 2040, consistent with the currently adopted Long-Range Transportation Plan (LRTP) of the Boston Region MPO, Charting Progress to 2040 (2015). For a full listing of the transit-related projects in the region included in the CTPS model for the 2040 1 I-90 Allston Interchange Project Draft Environmental Impact Report Ridership Forecasting Technical Report Design Year, please see Attachment C. The future improvements that are likely to have the greatest influence within or adjacent to the Project study area include: • Increased Service on the Worcester Main Line • Green Line Extension to College Avenue and Union Square in Somerville The 2040 No Build Alternative does not include the proposed West Station. Also, no significant changes in MBTA bus services within or adjacent to the project area are expected to occur by 2040 in the No Build Alternative. The 2040 Build Alternatives assume the opening of the proposed West Station, which would be a new stop on the MBTA’s Worcester/Framingham Line (Worcester Line) commuter rail service. MassDOT developed a proposed commuter rail schedule which meets the MBTA’s Service Delivery Policy1 of providing at least three morning and three afternoon peak period, peak direction train stops at the proposed West Station. The MBTA’s service policy also includes provision of 180-minute headways at a minimum during off-peak periods. The proposed Worcester Line schedule is included in Attachment C, and assumes that some Worcester Line trains would stop at the new Boston Landing Station at New Balance as well as at the proposed West Station. Several commuter rail peak period trains would run express through both stations. New Urban Rail train service was not incorporated within the ridership model horizon, because a future build year is not determined and service frequency has not been defined. The 2040 Build model scenarios tested various interchange and roadway network options, including the base interchange alternative, an interchange alternative that includes a new roadway connection to Commonwealth Avenue, and an alternative that restricts portions of Stadium Way for transit vehicles only (southbound between Western Avenue and Cambridge Street South). Bus service to West Station was also modeled, including the addition of new shuttle lines assumed to be operating in the project area. The shuttle bus assumptions incorporated into the CTPS model vary depending on the modeled scenario, as follows: • In the 2025 No Build, 2025 Build and 2040 No Build alternatives, one new shuttle bus route between Harvard Square and Barry’s Corner in Allston was assumed to operate at 10-minute headways during the daytime and 20-minute headways during the Night Period2. • In the 2040 Build base interchange alternative and the alternative with transit restrictions on Stadium Way, three new shuttle routes were assumed, including: o One new Harvard Shuttle route between Harvard Square and West Station, operating at 5-minute headways during the AM and PM Peak Periods, 15-minute headways during the Midday Period3, and 20-minute headways during the Night Period. o One new Kendall Shuttle route between Kendall Square and West Station via Central Square, operating at 5-minute headways during the AM and PM Peak 1 Massachusetts Bay Transportation Authority. Service Delivery Policy. June 2, 2010. www.mbta.com 2 Night Period: 6:00 PM to 6:00 AM 3 Midday Period: 9:00 AM to 3:00 PM 2 I-90 Allston Interchange Project Draft Environmental Impact Report Ridership Forecasting Technical Report Periods, 15-minute headways during the Midday, and 20-minute headways during the Night Period. o One new LMA Shuttle route between Ruggles Station and West Station via the Longwood Medical Area, operating at 5-minute headways during the AM and PM Peak Periods, 15-minute headways during the Midday, and 20-minute headways during the Night Period. • In the 2040 interchange alternative with a new roadway connection to Commonwealth Avenue, two new shuttle routes were assumed: o One new Harvard Shuttle route between Harvard Square and West Station, operating at 5-minute headways during the AM and PM Peak Periods, 15-minute headways during the Midday, and 20-minute headways during the Night Period. o One new Kendall-LMA Shuttle between Kendall Square and West Station via Ruggles Station and the Longwood Medical Area, operating at 5-minute headways during the AM and PM Peak Periods, 15-minute headways during the Midday, and 20-minute headways during the Night Period. Bus